From where I should do practice questions on c++

Answer 1

Start by finishing the c++ course here on Sololearn. Then do the 25 Solution Challenges here on Sololearn as well.

Answer 2

https://www.sololearn.com/discuss/1018847/?ref=app
https://www.sololearn.com/discuss/1099873/?ref=app
https://www.sololearn.com/discuss/529387/?ref=app
https://www.sololearn.com/discuss/2403741/?ref=app
https://www.sololearn.com/discuss/1041397/?ref=app
https://www.sololearn.com/discuss/1039026/?ref=app
https://www.sololearn.com/discuss/2877220/?ref=app